I'd be really happy to pick hair and eye color. That seems to be a really basic feature from the very first MMOs.
Currently you can only pick from the various hairstyles without further customization.

What other options do you guys think would be added in the future? And what is in your customization wish list

I personally wish there'd be an option to dye parts of your clothes to differentiate you from the rest of the world. I'd gladly pay for dyes in the cash shop if they make it available, and that's saying something coming from a completely F2P player like myself.